Kinetic Mechanisms for the Concentration Dependency of In Vitro Degradation of Nitroglycerin and Glyceryl Dinitrates in Human Blood: Metabolite Inhibition or Cosubstrate Depletion?

1989 ◽  
Vol 78 (4) ◽  
pp. 295-302 ◽  
Author(s):  
Saeho Chong ◽  
Ho-Leung Fung
1987 ◽  
Vol 253 (4) ◽  
pp. G477-G482 ◽  
Author(s):  
G. A. Eberlein ◽  
V. E. Eysselein ◽  
W. H. Hesse ◽  
H. Goebell ◽  
M. Schaefer ◽  
...  

Although cholecystokinin-58 (CCK-58) is a major molecular form stored in the intestine, it has not yet been shown to be released into the circulation. This report describes in vitro degradation of CCK-58 in human blood and plasma and the molecular forms detected when this degradation is inhibited. After incubation of CCK-58 for 150 min between 20 and 24 degrees C, approximately 60% of immunoreactivity recovered was degraded to smaller immunoreactive forms. Storage of the 150-min incubate at -20 degrees C for 3 days greatly increased the observed degradation to 85%. When CCK-58 was added in vitro to blood, similar degradation occurred. Degradation of CCK-58 could be inhibited by addition of acid. Blood was obtained 1 h after a test meal designed to stimulate CCK release. The pH was lowered during collection and processing of blood and plasma to inhibit in vitro degradation of cholecystokinin. This method permitted the detection of significant amounts of CCK-58 in circulation.


1974 ◽  
Vol 32 (02/03) ◽  
pp. 266-276
Author(s):  
Carl D. Jacobsen ◽  
John C. Hoak ◽  
Kenneth K. WU ◽  
Glenna L. Fry
Keyword(s):  

SummaryIn serum from patients with DIC at least 3 different FR-antigenic components could be found. It was difficult to demonstrate these components in the corresponding plasma samples. It is possible that a portion of these antigens formed as a result of in vitro clotting despite the presence of proteolytic inhibitors. These results suggest that the interpretation of “increased split products in serum” may be more complex than current concepts indicate.


1973 ◽  
Vol 30 (03) ◽  
pp. 494-498 ◽  
Author(s):  
G de Gaetano ◽  
J Vermylen

SummaryThrombelastograms of both native blood and re-calcified platelet-rich plasma samples taken from subjects given a single oral dose of aspirin (1 gram) were not significantly different from the pretreatment recordings. Aspirin also did not modify the thrombelastogram when preincubated in vitro with platelet-rich plasma at concentrations inhibiting the platelet “release reaction” by collagen. Thrombelastography therefore cannot evaluate the effect of aspirin on platelet function.


1973 ◽  
Vol 29 (03) ◽  
pp. 694-700 ◽  
Author(s):  
Paul L. Rifkin ◽  
Marjorie B. Zucker

SummaryDipyridamole (Persantin) is reported to prolong platelet survival and inhibit embolism in patients with prosthetic heart valves, but its mechanism of action is unknown. Fifty jxM dipyridamole failed to reduce the high percentage of platelets retained when heparinized human blood was passed through a glass bead column, but prolonged the inhibition of retention caused by disturbing blood in vitro. Possibly the prostheses act like disturbance. Although RA 233 was as effective as dipyridamole in inhibiting the return of retention, it was less effective in preventing the uptake of adenosine into erythrocytes, and more active in inhibiting ADP-induced aggregation and release. Thus there is no simple relation between these drug effects.


2001 ◽  
Vol 8 (6) ◽  
pp. 423-428 ◽  
Author(s):  
Krisztina Jost ◽  
Jozsef Varga ◽  
Botond Pence ◽  
Marta Zarandi

1963 ◽  
Vol 18 (5) ◽  
pp. 955-958 ◽  
Author(s):  
S. H. Blondheim ◽  
Gabriel Neumann ◽  
Edna Kott ◽  
Zena Ben-Ishai

The ability of human blood to acetylate p-aminobenzoic acid, determined in vitro, varied directly with the ambient temperature to which the subject was exposed before the blood was drawn. This was demonstrated by 135 determinations of the acetylating ability of the blood of 49 subjects performed over a period of 3 years, and also in acute experiments in which subjects were exposed to 6 and 37 C for up to 2 hr. Variations in the acetylating ability of blood may reflect the activity of metabolic mechanisms involved in thermal homeostasis. aromatic amines; p-aminobenzoic acid; cold; heat acclimatization; (blood) enzymes; weather; environment Submitted on September 11, 1962


Materials ◽  
2019 ◽  
Vol 12 (2) ◽  
pp. 295 ◽  
Author(s):  
Sébastien Champagne ◽  
Ehsan Mostaed ◽  
Fariba Safizadeh ◽  
Edward Ghali ◽  
Maurizio Vedani ◽  
...  

Absorbable metals have potential for making in-demand rigid temporary stents for the treatment of urinary tract obstruction, where polymers have reached their limits. In this work, in vitro degradation behavior of absorbable zinc alloys in artificial urine was studied using electrochemical methods and advanced surface characterization techniques with a comparison to a magnesium alloy. The results showed that pure zinc and its alloys (Zn–0.5Mg, Zn–1Mg, Zn–0.5Al) exhibited slower corrosion than pure magnesium and an Mg–2Zn–1Mn alloy. The corrosion layer was composed mostly of hydroxide, carbonate, and phosphate, without calcium content for the zinc group. Among all tested metals, the Zn–0.5Al alloy exhibited a uniform corrosion layer with low affinity with the ions in artificial urine.


2020 ◽  
pp. 128951
Author(s):  
Nadezhda Frolova ◽  
Alena Soboleva ◽  
Viet Duc Nguyen ◽  
Ahyoung Kim ◽  
Christian Ihling ◽  
...  
Keyword(s):  

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